Effect of Casting Parameters on Porosity in LFC

Abstract:

Cast aluminium alloys often contain microstructural defects resulting from the casting process such as porosity. Developments of Lost foam casting (LFC) process is considered as one of the most rapid in casting technology owing to its unique advantages on energy savings and capabilities to produce castings with thin sections. In the present research, experimental investigations in lost foam casting of aluminium-silicon cast alloy, LM6, were conducted. The main objective of the study was to evaluate the effect of different pouring temperatures, slurry viscosities, vibration times and sand sizes on the porosity of castings. A stepped pattern was used in the study and the focus of the investigations was at the thinnest 3 mm section. A full 2-level factorial design experimental technique was employed to plan the experiment and subsequently identify the significant factors which affect the casting porosity. The result shows that increasing in the pouring temperature decreases the porosity in the thin-wall section and finer sand size is more favourable than coarse size for LFC mould making process.

• Periodical: Applied Mechanics and Materials (Volumes 148-149)
• Pages: 1198-1201
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.148-149.1198
• Online since: December 2011
• Authors: S. Izman, Amirreza Shayganpour, M.H. Idris
• Keywords: Full Factorial Design (FFD), Lost Foam Casting, Porosity, Pouring Temperature, Sand Size, Slurry Viscosity, Vibration Time

References

[1] S. Farahany, M. Erfani: Artificial neural networks to predict of liquids temperature in hypoeutectic Al-Si cast alloys, J. Applied Sci., Vol. 10, pp.3243-3249. (2010)

DOI: 10.3923/jas.2010.3243.3249

[2] W. Griffiths, P. Davies: the permeability of Lost Foam pattern coatings for Al alloy castings, J. Mater. Sci., Vol. 43, p.5441–5447. (2008)

DOI: 10.1007/s10853-008-2844-2

[3] W. Jiang, Z. Fan: Investigation of microstructures and mechanical properties of A356 aluminium alloy produced by expendable pattern shell casting process with vacuum and low pressure, Materials and Design, Vol. 32, p.926–934. (2011)

DOI: 10.1016/j.matdes.2010.08.015

[4] A. Charchi: Numerical simulation of heat transfer and fluid flow of molten metal in MMA–St copolymer lost foam casting, J. Mater. Process. Technol., Vol. 210, p.2071–2080. (2010)

DOI: 10.1016/j.jmatprotec.2010.07.028

[5] T. Chakherlou, Y. Mahdinia: Influence of lustrous carbon defects on the fatigue life of ductile iron castings using lost foam process, Materials and Design, Vol. 32, p.162–169. (2011)

DOI: 10.1016/j.matdes.2010.06.015

[6] W. S. Ling, T. C. Thian: Process optimization studies for the dehydration of alcohol–water system by inorganic membrane based pervaporation separation using design of experiments (DOE), Separation and Purification Technology, Vol. 71, p.192–199. (2010)

DOI: 10.1016/j.seppur.2009.11.021

[7] G. Verran, R. Mendesb: DOE applied to optimization of aluminum alloy die casting, J. Mater. Process. Technol., Vol. 200, p.120–125. (2008)

[8] D. Gunasegaram, D. Farnsworth: Identification of critical factors affecting shrinkage porosity in permanent mold casting using numerical simulations based on design of experiments, J. Mater. Process. Technol., Vol. 209, p.1209–1219. (2009)

DOI: 10.1016/j.jmatprotec.2008.03.044

[9] S. Izman, A. Shayganpour, M.H. Idris: Analysis of the Effect of Sand Size and Vibration Time on Surface Roughness in Lost Foam Casting of LM6 Alloy by Design of Experiments, Advanced Materials Research, Vol. 337, pp.422-425. (2011)

DOI: 10.4028/www.scientific.net/amr.337.422

[10] Lei Deng, Xinyun Wang: Effect of porosity on dry sliding wear of Al–Si alloys, Tribology International Vol. 44, p.498–504. (2011)

DOI: 10.1016/j.triboint.2010.12.007